At any point of time, you can add upto 2 Bulk Actions. This implies that you would not be able to add another Bulk Registration / Transfer / Renewal / Suspend or Unsuspend / Lock or Unlock / Name Servers Modification / Contacts Modification (only for Customers) / Move Services / Privacy Protection Action, if 2 Bulk Actions are already running. You will encounter the below error message in case you try to do so:

Attention

You already have the maximum allowed number of Bulk Operations running. Please wait for at least one to complete before starting another.

You will be able to add another Bulk Action once one of the earlier actions has been processed completely.